.classIcon{
    text-align: center;
    width: 100%;
    height: 100%;
    position: absolute;
    left: 0;
    top: 0;
    color: #fff;
    opacity: 0;
}
.classIcon:hover{
    background: rgba(0, 0, 0, 0) -webkit-gradient(linear, left top, left bottom , from(rgba(27,188,155,0.42)), to(#1BBC9B)) repeat scroll 0 0;
    background: rgba(0, 0, 0, 0) -moz-linear-gradient(center top , rgba(27,188,155,0.42), #1BBC9B) repeat scroll 0 0;
    opacity: 0.85;
    transition: opacity 0.5s;
    -webkit-transition: opacity 0.5s;
}
.classIcon .btn{
    margin-top: 5%;
}